Shielding device for antifriction bearings



Aug. 26, 1952 Flled Aug l1, 1949 Aug. 26, 1952 E. R. wlLFLEY SHIELDINGDEVICE FOR ANTIFRICTION BEARINGS Filed Aug. 11, 1949 3 Sheets-Sheet 2TTO RN EY Aug. 26, 1952 E. R. WILFLEY 2,608,423

SHIELDING DEVICE FOR ANTIF'RICTION BEARINGS Filed Aug. ll, 1949 3Sheets-Sheet 5 FIC-L7.

,INVEN-ron: ELMER R. WILFLEY,

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ATTORNEY Patented Aug. 26, 1952 SHIELDING DEVICE FOR ANTIFRICTION,

BEARINGS Y Elmer R. Wiley, Denver, Colo., assignorY to A. R. Wililey andSons, Inc., Denver, Colo., a corpo-` ration of Colorado ApplicationAugust 11, 1949, Serial No. 109,710

4 Claims. 1

This invention relates to radial or journal bearings for rotary shaftsand more particularly to improvements in devices associated with thebearing block and with the shaft for preventing or discouraging entryinto the bearing of ldamaging material. More particularly, thisinvention relates to improvements in labyrinthine type ofbearing-protective shielding devices employing one xed and one rotarycomplementary labyrinthic members. .The narrow labyrinthic path betweenthese members together with centrifugal force set up by the relativemotion between the rotary and the xed member discourage entrytherebetween of bearing-damaging material.

It is among the objects of this invention to improve the effectivenessof such a shielding device by improving its centrifugal expelling orresisting action to suspended solids. That object is attainable by theuse of this invention which provides a rotary member that issubstantially cupshaped to surround and cap a cylindrical stationarydrum-like member extending from the bearing block, with a labyrinthinepassage between the members. The inner face of the rotary cup isprovided effectively; with ribs for expelling suspensions ofbearing-damaged material that may otherwise have a tendency to enterbetween the members. i

For example, such a journal shielding device is employable incentrifugal pumps for handling suspended solids thatare abrasive orcorrosive, known variously as sand pumps, sludge pumps, and slurrypumps, since in such pumps the radial bearing that supports the impellershaft nearest the pump housing is exposed to attack by such suspensionsthat may leak from the pump housing passed and along the impeller shaft.

lSuch a pump isexemplied in the patent to Wiley, No. 1,976,532, whichshows an axially non-shiftable impeller shaft encircled by an annularresilient diaphragm-like type of valve which is shiftable axially uponthe shaft for opening or closing a gap around the impeller shaft. Inthat patent, the shifting is veiiected automatically by valve-shiftingmechanism whereby the valve is normally held in closing position byspring pressure when the pump is not operating. When the impeller shaftstarts rotating, a Vset of centrifug-ally operated weighted leversfunction against the pressure of the spring, to shift the valve from itsclosing position and the valve remains open while the pump is running.Meanwhile, leakage through the annular gap is counteracted by anauxiliary impeller which is coaxial with the impeller shaft and rotatestherewith. Rotation of the` auxiliary impeller creates hydraulicpressure opposing the tendency of leakage of fluid through that gap.When the, pump stops running, the valve shifts gradually from open toclosing position due, to the spring pressure as the hydraulic Sealingpressure from the auxiliary impeller dies down along with the waning ofthe centrifugal force which otherwise shifts the valve against thespring pressure.

In that pump, a bearing shielding devceof labyrinthic type is disposedbetween the valveshifting mechanism and the bearing, and that devicederives supplementary protection against damaging fluids by a shell orskirt which ini that disclosure encloses` and rotates with the rotaryparts of the valve-shifting mechanism. Therefore, it is among theobjects of this invention to devise an arrangement such that theeffectiveness of the labyrinthic bearing-shielding device is renderedindependent of and non-reliant 'upon any protection derived from partsofthe valveshifting mechanism, so that such protective skirt can beeliminated.

Other objects include `Simplifying and rendering more compact suchbearing-shielding means for assuredly preventing suspended solids frominterfering with the proper `operation of the valve-shifting mechanismofthe pump.

Such a pump usually has its pump `housing fixed to a base and there is arotatable horizontal impeller shaft extending at one end into the pumphousing and at its other end by spaced-apart anti-friction bearingscarried one at the pump end of a tubular shell supported from the baseand one at the other end of the shaft with each bearing having a fixedpart or block: and a rot-ating part encircling and supporting the shaft.A cage is iixed to the pump-end of the shell and within the cage areautomatic centrifugally operated means for shifting or flexing theresilient valve into closing and non-closing positions. When in oneposition, because there is no stuffing box between the shaft and thepump housing, there is some leakage back into the cage of the suspensionbeing pumped, so it is one object of this invention to protect thepump-end bearing for the shaft against damage by contact therewith ofthe abrasive suspension or slurry.

In an embodiment of thisinventionthe centrifugally operated means in thecage for flexing the resilient valve comprise weighted levers supportedfrom a hub fixed on the shaft to rotate with it, and these levers attheir free non-weighted ends bear against a disc slidably mounted fromthe shaft that also rotates therewith to move the disc in one directionand spring means are provided for returning the disc to its initialposition. Since these spring means are also Within the cage, anotherobject of this invention is to protect them too against damage bycontact therewith of the abrasive suspension being pumped.

A further objectv is to assemble these parts for accomplishing theseVobjects so as to take up a minimum of length, while a still furtherobject is to assemble these parts in a way that makes for readydisassembly in case of need.

One of these objects is realizable by an assembly which comprisesproviding a flange-carrying stationary open-ended cylindrical drum-likemember extending toward thepumpA from the xed part of the bearingnearest the pump-housing With cylinder-capping cup-like means ex- 4drum-capping cup-like member looking from right to left in Figs. 1 and2. Fig. 5 is a partial isometric vieW of the member of Fig. 4. Fig. 6 isan enlarged detail of that member, while Fig. 7 shows enlarged detailsof that member and its cooperating fixed drum. y

In the drawings, the base II of the pump has two upright standards I2and I3. The pump housing, represented generally by the letter P, is madeup of removable and separable housing section I4 and housing section I5suitably held on each side of standard I2, together with antendingtoward that :bearing from the shaft and Y rotatable therewith. The xedopen-ended drum and the rotating cup means covering the open end portionof the cylinder function by means of centrifugal force exertedbythecupgto resist entrance of slurry, or other suspension being pumped,between the rotating cup and the fixed drum by impelling away therefromanysuch slurry that Would otherwise pass into the drum and thus reachthe bearing. 'This effect can be stimulated by coaction between certainkinds of projections extending outwardly on the drum leaving groovestherebetween and inwardly on the cup, but these will be described later.

Another of these objects i's realizable by providing for the cup, a hubextending toward the pump housing secured to `be rotatable with theshaft and carrying in such rotation the encircling spring and the discagainst which bears the spring and the centrifugally operated levermeans, and also providing a flexible cover for the spring contactedA bythe disc-and rotatable with the hub of the cup. Y

The foregoing structure gives such a pump structure that has a minimumlength, and another object is realizable by the'foregoing assembly plusa removable closure head on the pump-endfof thecage. Thus Awhen the pumphousing and thenthe impeller are removed as usual, the closure head'isthen removed from the cage with the shaft still in place, whereupon theoperator can'reach a set-screw securing the hub of the cap to the shaft.With this screw loosened, the operator can then pull or slide towardshim, the cup-carrying hub on which is supported an assembly comprisingthe pivoted levers, the disc against which they operate, the spring thatbears on that disc against pressure ofl the levers when centrifugallyoperated; and the flexible cover means on the spring. The fixed drumremains in place on the Ashaft after the hub-carried assembly .is thusremoved. v Other objects as well as features of advantage will appear asthis specification proceeds.

The best embodiment of thisinvention now known to me has been chosen asan example for illustration herein but it is to be understood thatchanges can be made so long as they or their equivalents fall within theambit of the appended claims.

Thisembodiment has been illustrated in the accompanying drawings inwhich- Fig. 1 shows a side elevation of my improved pump with parts insection. v Fig. 2 is a. vertical sectional enlarged view of thesectioned parts shown in section in Fig. 1. Fig. 3 is a partialisometric view of the resilient cover for the spring. Fig. 4 is a planView of the rotatable other housing part that is a contoured or conednose plate I6, which latter with the pump runner or impeller I'I isrotatably carried by impeller shaft I8 entering the pump housing andsupported at its other end from anti-friction bearings B1 and B2 held ina tubular shell I9 supported in turn from standard I3 uprising from thebase I I.

Supported from the left hand end of theshell I9 is a plate I 20Vcarrying an open-ended fixed drum-like' extension D contoured tovpresent exteriorly thereof a smaller end flange'ZZ and another largeriiange 23 with an inner circumferential solids-receiving groove 24therebetween. Between the larger flange 23 and the carrying platev 2U isa circumferential uncovered outer wider and deeper solids-receivinggroove 25. The open endof the' drum D is closed as at 2B by a stuing boxor equivalent sealing member to stop any suspended 'solids being pumpedfrom entering that openend.

Capping the open end of the drum D is a rotary cup-like expeller memberC having a cylindrical body portion 28 and a head or bottom portion 29through which passes a set-screw 30 for securing the cup to rotate withthe rotatable impeller shaft. I8. The head 29 of the cup terminatesl ina. hub 3| encircling the shaft. Frictionally encircling the hub is aresilient canvasreinforced diaphragm-like Valve V made' up of a neckportion'that grips the hub from which inclines a septum having alaterally extending flange F that is-much thicker than the septum andpresents a hat face. The septum flexes so that the flange can shift backand forth while the neck remains unchanged. Whenthe flange is flexed tomove toward the left, it engages in sealing or closing position with theannular ridge 32. While the neck remains unchangedly positioned on theshaft I8, the septum is flexed auto matically tothe left by spring 33that encircles the shaft I3 and normally bears against disc 3d (thatrotates with the hub 3|) to move it to the left and thus shift or ex thethickened flange F of the septum of the diaphragm V so that it con tactsthe sealing annular ridge 32 and is thus in Vclosed position. Disc 34 isslid or shifted in the opposite direction, against spring pressurethereon, vby means of centrifugally operated levers 35 pivoted at 36 andprovided With weights or Weighted arms l3'I. These levers are supportedfrom the hub 3Iby arms 38 rising from the hub 3|, so `the levers rotatewith the hub and disc'. The spring 33 is housed in a recess 39 which isclosed by a resilient and eXible Shielding cover S, preferably of rubbershaped as shown in' Fig. 3, and contacting'the disc 34, for thusprotecting or shielding the spring against slurry or. other suspensionthat `may leak from the pump Vhousing. `The diaphragm V, preferablyshaped as shown,.is held in place on the disc 34 by means of chamferedplate 40 suitably clamping vthe tapered lperiphery of the flange F- ofthe diaphragm to the disc.

Surrounding the hub 3l, are the disc 34 and the centrifugal levers 35,in a cage 4|, having a cylindrical body portion 42 secured to the shelll!! at one end, andv having its left hand end closed by ahub-bearing'head-plate 43 provided with a hub 44 terminating in a flange45. Between the bore of this hub and the hub 3l of the cup C is anannular gap or passage 46, flow of liquid through which is either.permitted or stopped by the position taken by the flexing or shiftingof flange E" on the septum of the diaphragm V. Preventing flow of airthrough that. passage inward to the pump is an auxiliary impeller 4'!comprising a series of curved or turbine-like blades depending from theflange 48 on the coned plate I6 that rotates with the impeller shaft I8,and cooperating in this air-excluding function with the flange 45 on hub44.

Cage 4l is held in place by fastening to a dished plate 49 fastened tothe pump housing section l5 and that in turn, with the cage, is held inplace on` 'that section of the pump housing by means of sleeve 50secured by screw-held lugs 5l. The cage 4l is apertured as at 52 and isopen at its bottom as at 52a to let out that quantity of suspension thatleaks thereinto from the pump housing when the flange F of diaphragm Vis open but even so, that suspension gets thrown onto the various partsthat are within the cage and there is a tendency otherwise for it tocreep into the bearings B1.

Referring now to Figs. 4 to 7, the means for capping the open-endedfixed drum D that is carried from the tubular shell I9 Ain which bearingB1 is mounted, comprises the cup-like eXpeller member C that has acylindrical body portion 28 and a closure head 29. Inwardly projectingfrom the head 2S are ribs or blades `53 that preferably extendnon-radially thereof, namely tangentially to the bore of that head.Inwardly projecting from the cylindrical body portion 28 of the cup Care ribs or blades 54 that preferably are shouldered as at 55 and theseribs also extend at a sloping angle away from the direction of motion ofthe rotatable cup. These ribs are shouldered at 55 so that the thickerpart of each rib barely clears the end flange 22 on the fixed drum D,while the thinner part of the ribs barely clears the larger flange 23 onthat drum. And in the same way, the bottom ribs 53 barely clear the endof the drum. This expeller cup C in rotating while in capping positionaround the open-ended .drum D expels any suspension that may tend toenter between these parts and thus shield the bearing B1 from suchabrasive suspension. The angularity of the ribs are helpful in this dueto centrifugal action and the circumferential grooves 25 and 24 on thehub also have an advantageous effect in such expelling.

In operation, as the impeller shaft starts up,

lspring 33 still presses diaphragm valve V into closing position in theannular passage 46 between the interior of the pump housing P and thecage 4l. But as soon as the shaft gathers momentum, centrifugal forceoperates upon the weighted levers 35 to swing their weights outwardly,whereupon the short ends of the levers force the disc 34 to the rightovercoming pressure of the spring 33, and this causes the diaphragmvalve V to slide to the right and thus open the passage 46 to permitcertain leakage into the cage 4|, as before described. It is to shieldthe bearing B1 and the spring 33 from such leaking susl 's pended solidsor slurry, that one purpose of this invention. Il r` i In thispumpingioperation, the shaft I8 rotates and with it also rotatesunitarilythe diaphragm V, the disc 34, the levers 35, andspring 33 andthe cup C, because they are all `carried by hub 3| (of cup C) fastenedto the shaft by the setscrew 35; The cup rotates in end-capping positionaround fixed open-ended drum D that is supported from the tubular shelll9 in which the Vbearings for the shaft are mounted. Rotation of the cupsets up centrifugal force between its interior and the exterior of thedrum, which is stimulated or emphasized Aby the interior `blades or`ribs on the cup, so that positive and forceful expelling action takesplace that shields the bearing B1 from any slurry or other-suspensionreaching it. The inclined blades or ribs`54 are essen; tial to theoperation, especially at the entrance to the `expeller C.Practicallynothing gets into the expeller until the outsidegroove 25fills up with solids, and when thishappens, `then the blades or ribsbecome llooded and material goes back. If and when the expeller and thegrooves 25 and then 24, as well as `the blades, become completely packedwith ordinary mill tailings, as they sometimes do, a hose is turned onthem :for a while when running, and all the solids are washed therefrom.So an important feature of this invention is the location of theinclined blades or ribs 54 of the expeller C at the outer `edge of theoutside uncovered circumferential groove 25. Since the cage has slurryin it, and rotation of the parts housed within the cage tend to getcovered with the slurry passing the diaphragm V, another feature of thisinvention is the provision of the rubber cover S for the spring betweenit and the disc 34, which latter keeps the cover closely enclosing thatspring, and thus shielded from the slurry.

Another feature of this invention is the compactness with which thisassembly can be made to condense the overall length of the pump. Andstill another feature is the ease of disassembly of within the cage. Anoperator to disassemble the parts removes the pump housing sections I4and I 5, whereupon he slides off to the left, the coned nose plate I6from the impeller shaft I8. iThis exposes the dished plate 49 which isreadily removed by unscrewing the screws that hold it to the head plate43 of the cage. That plate in turn is readily removed from thecylindrical portion 42 of the cage by unscrewing the screws that holdthose parts together. Thereupon, the operator can push his wrenchthrough the open end of the cage 4l to reach the set-screw 30 and loosenit, after which he slides out from the cage and assembly that that screwholds fast to the shaft I8, namely, the hub 3| with its drum-capping cupC, the disc 34, the centrifugal levers 315, the spring 33 and its coverS, and the diaphragm valve V. After such unitary removal, the individualelements of the assembly can either be separately removed or inspected.Restoration of the parts is in the reverse order of disassembly.

I claim:

1. A shielding device for an anti-friction bearing having a supportingcasing and a rotatable part encircling and supporting a rotatablehorizontal shaft; drum means extending from the casing having acircumferential suspended-solids receiving groove; and horizontallyextending drum-capping means rotatable with the shaft for expellingsuspended solids away from entry into the space between the drum and theshaft as well 'as into the solids-receiving groove including shoulderedribs extending toward the drum while sloping away from its direction ofrotation and terminating at the edge of the groove.

2. A shielding device for an anti-friction bearing having a supportingcasing and a rotatable part encircling and supporting a rotatablehorizontal shaft; drum means extending from the casing having acircumferential suspended-solids receiving groove having exteriorlythereof a plurality of flanges of which one extends from the drum agreater distance than the other; and horizontally extending drum-cappingmeans rotatable with the shaft for` expelling suspended solids away fromentry into the space between the drum and the shaft as Well as into thesolidsreceiving groove including ribs extending toward the anges on thedrum.

3. A shielding device for an anti-friction bearing having a supportingcasing and a rotatable part encircling and supporting a rotatablehorizontal shaft; drum means extending from the casing having acircumferential suspended-solids receiving groove; and horizontallylocated drumcapping means rotatable with the Shaft for ex- REFERENCESCITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,145,516 Schmid-Roost July `6,1915 1,395,480 Burchart Nov. 1, 1921 1,876,656 Forsberg Sept. 13, 19321,976,532 Wililey Oct. 9, 1934 1,978,239 Wheeler Oct. 23, 1934 2,092,351Huntzicker Sept. 7, 1937 2,240,782 Jacobsen May 6, 1941 2,272,454Wilfley Feb.l 10, 1942A

